CVE-2009-3677 - CVE House
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Status published Critical CVE-2009-3677

The Internet Authentication Service (IAS) in Microsoft Windows 2000 SP4,...

Vulnerability Description

The Internet Authentication Service (IAS) in Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP2, Vista Gold and SP1, and Server 2008 Gold does not properly verify the credentials in an MS-CHAP v2 Protected Extensible Authentication Protocol (PEAP) authentication request, which allows remote attackers to access network resources via a malformed request, aka "MS-CHAP Authentication Bypass Vulnerability."

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

windows 2000, windows server 2003, windows server 2008, windows vista, windows xp
Vulnerable Versions:
Unknown

Timeline

Official Publish: December 9th, 2009
Last Modified: August 7th, 2024
Added to House: July 19th, 2026

CVSS Vectors

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.